One card is drawn from a pack of 52 cards. What is the probability that the card drawn is either a red card or a king ?

Answer: Option C

Here, n(S) = 52
There are 26 red cards (including 2 kings) and there are 2 more kings.
Let E = event of getting a red card or a king.
Then, n(E) = 28
$$\therefore P(E)=\frac{n(E)}{n(S)}=\frac{28}{52}=\frac{7}{13}$$